8 AUSTRALIAN ECONOMIC HISTORY 
anything in the nature of efficient direction of capital investment 
became an utter impossibility. Thus the search for profit and 
the hectic prosperity of the community led, on more than one 
occasion, to reckless speculative investment in land, since all 
economic undertakings were already well supplied with capital. 
Taking all these factors into account, it is no exaggeration 
to say that we have here the ideal situation demanded by Viner 
in which the overseas trade of the community is of overwhelming 
importance in relation to its internal trade, and to its industry 
and commerce in general, a situation which is especially favour- 
able for the accurate analysis and measurement of the ‘effects 
on each other and on the commercial and industrial structure 
of a country of the factors at work within the mechanism of its 
external trade’. But, despite the comparative ease in the isola- 
tion of the main controls, there are certain inherent difficulties 
involved in such measurement that must not be underrated. 
For the purposes of induction the limitations in the knowledge 
of the specific facts due to inaccurate or inadequate data of a 
statistical character, especially for the early period of Australian 
history, is a prime difficulty. Apart altogether from inadequacy 
of the statistical material, other difficulties may be indicated ; 
and the chief of these is the difficulty of ‘isolating the causes 
of a complex and joint effect’. The method of concomitant 
variations is sufficiently difficult of application in the carefully 
controlled circumstances of the laboratory, but in the tangled 
skein presented by a trade situation the difficulties are vastly 
enhanced. Again, regard must be paid to the fallibility of the 
human factor in the work of collecting, manipulating, and in- 
terpreting the statistics. Finally, the difficulty which faces a 
single investigator under the necessity of holding all the threads 
in proper order while engaged in the work of re-arranging and 
re-estimating the value of the data is almost insuperable.